Suzuki DF 40 Service Manual page 205

Install crankcase to cylinder.
Apply engine oil to crankcase bolts.
Tighten crankcase bolts in three (3) steps following the order
indicated below.
NOTE:
After tightening crankcase bolts, check to be sure that crank-
shaft rotates smoothly when turned by hand.
Crankcase bolt
1st step 8 mm
10 mm
2nd step 8 mm
10 mm
Final step 8 mm
10 mm
UPPER OIL SEAL HOUSING
Apply engine oil to lip area of upper oil seal.
Install upper oil seal housing and secure with bolts.
5 N . m (0.5 kg-m, 3.6 lb.-ft.)
11 N . m (1.1 kg-m, 8.0 lb.-ft.)
20 N . m (2.0 kg-m, 14.5 lb.-ft.)
42 N . m (4.3 kg-m, 31.0 lb.-ft.)
25 N . m (2.5 kg-m, 18.1 lb.-ft.)
53 N . m (5.3 kg-m, 38.3 lb.-ft.)
POWER UNIT 6-62
Tightening order
8
16
12
4
9
1
13
5
7
15
3
11
2
10
14
6